Two new saltmarsh vegetation species records for Kangaroo Island

The surveys are expected to highlight the changes that have taken place in vegetation species composition on the Island and in great reward for the research team – two new saltmarsh vegetation species have already been recorded!

With additional funding support from the SA Coast Protection Board, Doug Fotheringham, a research fellow from Herbarium SA was contracted to lead the surveys.

Doug, a former Senior Scientific Officer with the Coast Unit, developed the methodology and undertook the baseline surveys as part of a larger program to map and describe the extent of saltmarsh and mangrove habitats across South Australia. Saltmarsh and mangrove communities are considered a vital component of the coastal system, providing many ecosystem functions, including protecting our shorelines, providing important marine being identified as a climate change indicator and important carbon sinks where they can sequest carbon and store it within their sediments for millennia.

Subtropical and temperate coastal saltmarsh communities are under increasing threat of degradation and have been listed as a vulnerable threatened ecological community under the EPBC Act 2005, placing further emphasis on the need to assess their condition in South Australia.

After 30 years, the surveys are expected to highlight the changes that have taken place in vegetation species composition which is closely linked to changes in climatic conditions, including sea level rise, land subsidence, and anthropogenic pressures as well as predicting future changes in response to predicted sea level rise.

Already, the project has identified two new saltmarsh species records for Kangaroo Island, Tecticornia indicassp bidens and T. indica ssp leoistachya, The plants were identified as T. indica in the field but there was some uncertainty because the species is not listed as present on the island. The ID has since been confirmed by Ron Taylor a plant collector with good knowledge of Tecticornia’s.

Coastal Scientific Officer Alison Turner said the project has been a valuable opportunity for shared learnings between Coast Unit staff, regional KI staff and researchers from the University of Adelaide's Future Coasts Lab.

"The Future Coasts Lab undertook soil cores within key coastal wetland habitats as part of the vegetation surveys to measure sediment carbon stocks in several coastal saltmarsh locations along the east coast of Kangaroo Island, an under-sampled region of the state for blue carbon, with no previous data," Alison said.

“Thanks must also go to DEW staff on KI and to the private landholders who supported access to their land to undertake this work. These recent surveys provide an opportunity to identify and quantify any change in these systems, as well as predict the potential impacts future changes may have on these communities."

Additional saltmarsh vegetation surveys were also undertaken within Bay of Shoals and Strawbridge Point saltmarsh ecosystems in the eastern end of Kangaroo Island and are part of broader ongoing coastal monitoring being undertaken by the DEW Coast Unit across the state.